Diffusion/Chemical Reaction/Spectrometric Device for the Analysis of Petroleum Hydrocarbons in Environmental and Geological Formation Samples

ABSTRACT

An analytical device that provides chemical composition spectrometric data on surface and sub-surface samples is provided. The device provides for the introduction of the liquid or solid sample into a sample chamber where it is extracted by a chlorinated hydrocarbon solvent. The extract then passes into a chamber where it undergoes a Friedel-Crafts (FC) reaction, catalyzed by a polymer-encased Lewis acid. This FC reaction produces characteristic colors, which provide specific quantitative and qualitative chemical information about the hydrocarbon substance. The polymer chain then passes into a module containing a spectrometer consisting of a tungsten/halogen light source, a diffraction grating, and a CCD-based detector that reads the spectral information and sends the digital information to a microprocessor. The microprocessor is not described in this patent application as many types exist, which will perform the necessary operations for analysis, storage, and transmission of the spectral data.

BACKGROUND OF THE INVENTION

The present invention relates generally to the analysis of hydrocarbonsin environmental or geological samples. The analytical spectral dataproduced by the invention is based on the original U.S. Pat. No.4,992,379 of the present inventor. Robust chromophores in theultraviolet and visible regions of the electromagnetic spectrum areproduced by Friedel-Crafts reactions with a wide variety of the chemicalconstituents in crude oil and crude oil fractions. These chromophoresserve as spectral “markers” which fingerprint the petroleum substanceallowing for a determination of type or source of the substance. Thisfingerprinting of the substance provides vital information forenvironmental investigation and assessment. It also serves as extremelyvaluable information in the Oil & Gas Exploration and Production (E&P)industry in the search for, and efficient production of, petroleum.

The utilization of field kits for environmental testing of hydrocarbonsbased on the inventor's U.S. Pat. No. 4,992,379 (Hanby, Feb. 12, 1991)has proven of considerable value. The addition of a “read-out”spectrometric device to display and interpret the chromophoric signalsproduced by that test kit method will greatly enhance the use andutility of the kits. This proposed development was recognized by theU.S. Dept. of Commerce in its “Rapid Commercialization Initiative”Program in 1997 when the Hanby methodology was selected as one of the“Ten Best Environmental Developments in the United States”. Developmentof a prototype read-out device for the Hanby Test Kits in thatconfiguration was accomplished and the device was laboratory and fieldtested by the EPA and the U.S. Army Corps of Engineers Cold RegionsResearch and Engineering Laboratory. (See:http://www.crrel.usace.army.mil for (2) technical reports: ERDC/CRRELTR-007 and TR-00-20 for evaluations of the Hanby kits and H.E.L.P.MATE2000 instrument.)

SUMMARY OF THE INVENTION

Precise and accurate quantitative and qualitative chemical analysis bythis Chemical Reaction Spectrometric (CRS) method is primarily dependenton the stoichiometric relationship of the FC-reactive components.Secondarily, the bulk amount and anhydrous state of the catalyst has adirect relationship on the quantitative determination in this method.The encapsulation of the catalyst in a permeable polymer tape representsa significant modification of this technology. Encapsulation in thepolymer serves two important and unique modifications to theFriedel-Crafts reactions on which this new spectrometric method isbased. The polymer is hydrophobic and oleophilic, thus providing theimportant functions of protecting the Lewis acid catalyst from water inthe samples and allowing controlled diffusion of the FC-reactivecomponents of the sample into the catalyst. These significantmodifications of the invention provide necessary chemical and spectralspecificity enabling precise chemical quantitative and qualitativeanalysis. The present invention has (2) application configurations: 1) ahand-held device for transport to the field for soil or water analysisor, 2) it can be transported downhole as part of a wireline tool, withappropriate thermal protection, and electronic signal transmission forthe analysis of geological fluids. These and other features andadvantages of the present invention will be more readily understood bythose skilled in the art from a reading of the following detaileddescription.

DESCRIPTION OF THE (3) DRAWINGS

Drawing 1/3 illustrates the invention and provides a sequentialdescription of the steps involved in its operation as an analyticalextraction, chemical-reaction (colorimetric), and spectrometric device.The following steps describe the sequence of operation. The severalcomponents of the invention are enumerated in drawing as 1/3, 2/3/, 3/3.The details of the optical components of the CCD spectrometer are shownin drawing 2/3. The valving arrangement is detailed in drawing 3/3.

Step 1. Liquid or solid samples are introduced into the Sampleextraction chamber, III, via the Sample access, II

Step 2. Withdrawal of the Dual channel syringe, I, causes a smallaliquot of the CCI₄ extraction solvent from the CCI₄ Solvent reservoir,IV, to inject into the Sample extraction chamber, III.

Step 3. Depression of the syringe and simultaneous pressing of the SECmanual valve, IIIA, causes the aliquot of the CCI₄ to be injected by theleft-hand channel of the syringe from the extraction chamber into theExtract/Catalyst Reaction Chamber (ECRC) V.

Step 4. Electronic activation (not shown) of the Motorized catalyst tapestorage disc drum, X, causes one segment of the catalyst tape, VI, toadvance, thereby positioning a catalyst packet under theTungsten/Halogen Probe, VII.

Step 5. Electronic activation of the Tungsten/Halogen Probe, VII, alsoactivates the Charge Coupled device (CCD) spectrometer, VIII, whichcauses a digital signal to be sent to the computer (not shown) via theUSB port (not shown).

Step 6. Manual depression of the ECRC drain valve (shown in drawing,(3/3) drains the extract into the extract waste storage reservoir, XI.

Flushing of the analytical stream channels and components, when requiredis accomplished by following these steps without introducing a sample.Either prior to, or after flushing permits obtaining a spectrometricblank as needed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is based on the generation of robust, transientchromophores generated by sigma and pi electrons that engage in bondformation in Friedel-Crafts reactions. These chromophores resonate withfrequencies in the near ultraviolet (UV) and visible (Vis) portions ofthe electromagnetic spectrum generated by a tungsten/halogen energysource.

In the present method and apparatus a soil, water, or formation fluidsample is extracted with an alkyl halide extractant. An especiallypreferred extractant solvent is carbon tetrachloride. The extractsolution is then caused to undergo Friedel-Crafts (FC) reactions byexposure to a Lewis acid catalyst. An especially preferred Lewis acidcatalyst is anhydrous Aluminum Chloride. The present invention describesapparatus that can accept the sample(s), the extraction solvent, a meansfor introducing the sample(s) and solvent into an extraction chamber, ameans for presenting a precise amount of the catalyst to the extractedsample solution, a tungsten/halogen source, and a charge-coupled-device(CCD) spectrometer for the detection of the signal generated by theFC-produced chromophores.

With reference to Drawing 1 the invention operates by introducing asample (soil, water, or formation fluid) via the sample access (II) intothe sample extraction chamber (III) using the dual channel syringe (I).The syringe is equipped with valves (see Detail drawing (3/3) thatregulate the flow of solvent from the CCI₄ solvent reservoir into thesyringe and, subsequently, into the Extract/Catalyst Reaction Chamber(ECRC) (V) The catalyst tape (VI) is fed into the ECRC (V) by themotorized catalyst tape storage drum (X). After a precise time andextraction temperature, which determine the diffusion of the solventextract into the polyethylene-enclosed catalyst, the chromophoric signalis read by the CCD spectrometer (VIII) (See detail drawing 2/3). Thedigitized signal from the CCD is electrically transmitted via a standardUSB connection from the electronic module (not shown) to a computer orother microprocessor-based read-out device.

The embodiment described is designed as a small-sized device such thatit can be easily transported to the field and utilized manually by oneperson for soil or water analysis for petroleum contamination.Conversely, this small device can be fully automated with appropriateelectronic operation of syringe and valving, and utilized withappropriate thermal and vibration insulation as a downhole wirelinedevice for oil exploration purposes (geological formation fluidanalysis).

Many modifications and variations, particularly in regard to automatedor remote actuation, as specifically mentioned in the embodied deviceand method may be made without departing substantially from the conceptof the present invention. Accordingly, it should be clearly understoodthat the form of the invention described herein is exemplary only, andis not intended as a limitation on the scope thereof.

I claim for patent:
 1. A device for on-site analysis of soil, water, orgeological fluids, which provides a method for performing sampleextraction, catalytic presentation, and spectrometric signal productionas exemplified in the accompanying drawings and comprising thefollowings steps: introducing a soil, water, or geological formationfluid into an analytical device, which provides a method of extractingthe said sample(s) with an alkyl halide extracting solvent; delivering aprecise volume of the said alkyl halide solvent into the device suchthat a stoichiometric relationship is established with the sample;extracting the said sample in a chamber in the device using the saidextracting solvent; delivering the sample extract into a catalystreaction chamber; introducing a polymer-encapsulated Lewis acid catalystinto the said extracting chamber in a controlled temperature for acontrolled time such that the ensuing Friedel-Crafts reaction caused bythe catalyst, which is contacted by the solvent-extracted sample, togenerate specific chromophores, which quantitatively and qualitativelyidentify the sample chemically; illuminating the chromophoric signalsproduced from the chromophores using a tungsten/halogen probe; readingthe spectral signals generated by the sample using a CCD-basedspectrometer; transmitting the digital signal via a USB port fortransmission to a computer.
 2. A method of encapsulating a Lewis acidcatalyst in a polyethylene tape such that the said tape can beintroduced in a time and temperature controlled manner such thatspecific Friedel-Crafts reactions occur, which generate chromophoricproducts that provide spectrally definitive signals to preciselyidentify and quantify the analyte substance.
 3. A method ofencapsulating a Lewis acid catalyst in a polymer such that the catalystcan be maintained in an anhydrous state so that it remains active tocatalyze Friedel-Crafts reactions.
 4. A method of encapsulating a Lewisacid catalyst in a polymer such that diffusion of Friedel-Craftsreactive liquids occurs into the polymer in a precisely controlled timeand quantity so that the reaction occurs in a repeatable manner.
 5. Amethod of controlled presentation of catalyst-enclosed polymer capsulessuch that they are illuminated by a tungsten/halogen lamp.
 6. A methodof causing the spectrometric signal generated by Friedel-Crafts productsto be transmitted through a polymer tape in a time and temperaturecontrolled environment such that the signal can be dispersed through adiffraction grating and transmitted to a linear array charge-coupleddevice for electronic transmission of the digitized signal to amicroprocessor device.
 7. A method of storing a polymer tape, whichcontains encapsulated Lewis acid catalyst packets, which is maintainedin an anhydrous condition and coiled on a feed drum to be sequentiallyintroduced into a reaction chamber for subsequent exposure toFriedel-Crafts reactants.
 8. A method of using a dual-channeled syringeapparatus to withdraw an alkyl halide solvent from a storage reservoirfor subsequent introduction into an extraction chamber for extracting asoil, water, or geological formation fluid sample.
 9. A method ofvalving arrangement such that the alkyl halide solvent can betransmitted from one channel of the dual-channel syringe into anextraction chamber, thence transmitted to a diffusion/reaction chamber,thence to a spectrometer viewing module, and then to a waste reservoir.